A pressure detector which utilizes the MEMS technique has been proposed. This pressure detector employs a variable capacitor. More specifically, the variable capacitor is covered by a pressure sensor (pressure-sensitive film) which displaces according to pressure. The pressure sensor is connected to an upper electrode of the variable capacitor, and the upper electrode of the variable capacitor is displaced according to the displacement of the pressure sensor. With this structure, the capacitance of the variable capacitor varies according to the pressure and thus the pressure can be detected.
The above-described pressure detector contains a cavity within the pressure sensor. Because of this structure, the strength of the pressure sensor is not high. Therefore, if an object contacts thereto, the pressure sensor is adversely affected, making it impossible to perform accurate pressure detection.
Under these circumstances, there is a demand for a MEMS device which can inhibit the contact of an object to the pressure sensor.